SACRAMENTO, Calif. — California would allow noncitizens to serve on juries under a proposal being considered by state lawmakers, potentially expanding a fundamental obligation of American life to millions more people.

The measure, which would apply only to legal residents, would make California the only state to open the jury box to noncitizens who meet all other requirements of service, according to legal experts.

The proposal raises the question of what it means to be judged by peers in a state where more than one in seven residents is not a citizen.

One of the bill’s authors, Democratic Assemblyman Bob Wieckowski, said the proposal would help ensure an adequate pool of jurors, help immigrants integrate into American society and make juries more representative of California.

Story continues below advertisement.

Juries “should reflect our community, and our community is always changing,” Wieckowski said. “It’s time for California to be a leader on this.”

The Assembly passed the bill this week on a party-line vote, with most Democrats lining up in favor and Republicans standing in opposition.

Republican Assemblyman Rocky Chavez, who voted no, said the measure was unfair to the prospective jurors and any defendants whose fates they could decide. Resident aliens may not want the responsibilities of American citizenship, he said, and people on trial should not be judged by jurors who “might not have the same cultural experience.”

The legislation goes next to the Senate. Gov. Jerry Brown has not taken a public position on the bill.

There are roughly 2.5 million adults in California who live here legally but are not citizens, according to statistics from the U.S. Census Bureau and the Department of Homeland Security. Wieckowski’s bill, AB 1401, would not change other conditions for jury service; those eligible must still be at least 18, proficient in English and have no felony record.

Legal and trial experts had mixed reactions to the measure, which would open a distinctly American institution to people not legally classified as Americans. Legal proceedings, particularly civil cases, in many parts of the world are not decided by a jury.

“The real goal is to have people in the community make a determination about guilt or innocence. There could be a value in adding different perspectives into the deliberation process,” said Matthew McCusker, president of the American Society of Trial Consultants.

But noncitizens may not have the same understanding of the judicial system, he said.

“Jury instructions are remarkably complex,” McCusker said. “If you add in further barriers, whether it’s language or cultural, you’re adding more difficulties in following the rule of law.”

Niels Frenzen, a professor of immigration law at the University of Southern California, said he doubted immigrants would have any more trouble handling jury duty than citizens would.

“There is not often that great a divide of knowledge between immigrants and … citizens.”